PPD-Construction
Light shelf
-a horizontal surface placed above eye level that reflects direct daylight onto the ceiling while shading the lower portions of the window and the interior of the room. -distributing the light more evenly from the window to the back of the room. -should have a diffuse and highly reflective surface. glass with a higher VLT can be used above the shelf, while tinted glass may be specified below for glare control.
Principles of refrigeration
-compressive refrigeration -absorption -evaporative cooling, can be used in some climates to produce cool air
boiler
A boiler uses fuel to create hot water or steam. The fuel source can be gas, oil, electricity, or steam.
Bulk plane restriction
A bulk plane restriction is a zoning technique that establishes an imaginary inclined plane beginning at the lot line or the center of the street at a given elevation and slopes at a prescribed angle toward and over the lot. The building cannot extend beyond this plane. This restriction ensures adequate light, air, and solar access for neighboring properties and for the open space and streets around the land.
circular mil
A circular mil is a derived area measurement representing the square of the cable diameter in thousandths of an inch (mils). The current-carrying capacity (or ampacity) of a conductor depends on its size, the type of insulation around it, and the surrounding temperature.
Heat pump efficiency
A heat pump's heating efficiency decreases as the outdoor air temperature decreases. At exterior temperatures below about 40°F, a heat pump is not economically competitive with oil or gas as a heating source. Heat pumps are more effective in mild climates where winter temperatures are usually moderate.
Conductivity
A material's thermal conductivity, k, is the rate at which heat passes through 1 ft 2 of a 1 in thickness of the material when the temperature differential is 1°F.
met
A met is the energy produced per unit of surface area per hour by a seated person at rest. One met is 18.4 Btu/hr-ft 2 .
product category rule
A product category rule is a set of guidelines for a particular type of product that establishes what data should be collected in the LCA, how LCA results are reported, and what other information must be reported in the EPD.
Smoke damper
A smoke damper is a listed device installed in ducts and air transfer openings that is designed to resist the passage of smoke. There are also combination fire/smoke dampers.
Thermal gradient
A thermal gradient shows variance in temperature through a cross section of a construction assembly
A ton of cooling
A ton of cooling is the cooling effect obtained when 1 ton of 32°F ice melts to water in 24 hours. This is equivalent to 12,000 Btu/hr.
VRF
A variable refrigerant flow (VRF) system uses a single compressor and condenser unit located outdoors, connected to multiple evaporators located in different zones of the building.
conductor sizes
AWG sizes range from 16 gage to 0000 (4/0)gage. The actual size of the conductor increases as the number designation decreases, so 16 gage is the smallest size (0.0508 in diameter), and 4/0 is the largest (0.460 in diameter). A single insulated conductor, no. 6 AWG or larger, or several conductors assembled into a single unit, is referred to as cable. Conductors no.8 AWG and smaller are called wire.
acidification
Acidification is the generation of waste materials that can lower the pH of surrounding waterways or soil.
Adsorption filter
Adsorption filters remove unwanted gases from the air with activated carbon
Toilet stall toe clearance
All toilet stalls must have toe clearance below the front partition and below at least one side partition. This clearance must be a minimum of 9 in above the floor and extend a minimum of 6 in beyond the compartment-side face of the partition.
radiative cooling
Also known as nocturnal cooling or night-cooled mass. A passive or active design strategy that uses thermal mass to collect and store heat during the day for release at night. This works best in climates where there is a significant difference between daytime and nighttime temperatures, such as the southwest and temperate climates.
All-air system
An all-air system cools or heats a space using conditioned air alone.
Evaporative cooler
An evaporative cooler (also called a swamp cooler) reduces the temperature of the air but does not reduce the enthalpy (total heat).
Heat gains from lighting
Because 1 W = 3.41 Btu/hr, heat gains from lighting can be calculated by multiplying the total wattage load of the building's lighting by 3.41. A general rule is to multiply the Btu/hr generated by these types of fixtures by 1.25.
Cellular metal floors
Cellular metal floors are a part of the structural floor. This is essentially metal decking designed for use as cable raceways.
Compressive refrigeration
Compressive refrigeration is based on the transfer of heat during the liquefaction and evaporation of a refrigerant. As a refrigerant in a gaseous form is compressed, it liquefies and releases latent heat as it changes state. As the same liquid expands and vaporizes back to a gas, it absorbs latent heat from the surroundings into the gas.
Conductance
Conductance, C, is the same property when the material is a thickness other than 1 in.
Energy star
ENERGY STAR also offers a voluntary labeling program designed to identify energy-efficient products such as consumer appliances, office equipment, residential furnaces and air conditioning equipment, lighting, and consumer electronics.
Electric metallic tubing
Electric metallic tubing (EMT) is the lightest of the three and is installed with special pressure fittings because it is too thin to thread.
Electricity as energy source
Electricity has many advantages as an energy source. It is easy and relatively inexpensive to install, simple to operate, easy to control, and flexible in zoning. It does not require storage facilities, exhaust flues, or supply air. Electricity has an equivalent heating value of 3413 Btu/kW.
Electronic filters
Electronic filters trap particles by creating different electrostatic charges between the particles and the filter.
Eutrophication
Eutrophication is the formation of excessive nutrients in a body of water that promotes increased algae growth.
Flexible metal-clad cable
Flexible metal-clad cable, also known by the trade name BX, consists of two or more plastic-insulated conductors encased in a continuous spiral-wound strip of steel tape.
forced air furnaces
Forced air furnaces come in three types: upflow, downflow, and horizontal
Oil grade
Grades with lower numbers are more refined and thus more expensive. No. 2 fuel oil is the grade most commonly used in residential and light commercial boilers, while no. 4 and no. 5 grades are used in larger commercial applications. The heat value for no. 2 oil is from 137,000 Btu/gal to 141,000 Btu/gal, while no. 5 has a heat value from 146,800 Btu/gal to 152,000 Btu/gal.
Green seal
Green Seal is an independent, nonprofit organization that strives to achieve a more sustainable world by promoting environmentally responsible production, purchasing, and products. Among other programs, Green Seal develops environmental standards for products in specific categories and certifies products that meet these standards.
GreenFormat
GreenFormat is a web-based database developed by the Construction Specifications Institute (CSI) to allow manufacturers to self-report sustainability properties of their products using a standard questionnaire format.
what does heat pump do
Heat spontaneously travels from warmer locations to cooler ones. A heat pump is a device that can reverse this, absorbing heat from a cooler location and transferring it to a warmer one, using the principles of refrigeration. A heat pump can provide heat in the winter and cooling in the summer.
Area Factor Increase Based on Frontage
If at least 25% of the building's perimeter is located on a public way or open space, the basic allowable area may be increased. the public way or open space must be at least 20 ft wide.
impedance
In AC circuits, resistance is known as impedance, which comprises both resistance and reactance and causes a phase change difference between voltage and current. The difference is represented by the power factor (pf) and can be a significant factor in calculating power in an AC circuit.
Upflow furnace
In an upflow furnace, the return air is supplied at the bottom of the unit and the heated air is delivered to the bonnet above the furnace where it is distributed through ductwork.
Intermediate metal conduit
Intermediate metal conduit (IMC) has thinner walls but the same outside diameter as rigid steel conduit. It is also installed with threaded fittings.
Heating value of propane
It is delivered and stored in pressurized tanks and has a heating value of about 21,560 Btu/lbm, or 2500 Btu/ft 3 .
Latent heat
Latent heat gain in residential and many other occupancies is about 30% of the sensible heat gain.
Mean radiant temperature (MRT)
MRT is a weighted average of the various surface temperatures in a room and the angle of exposure of the occupant to these surfaces, as well as of any sunlight present.
Heating value of natural gas
Natural gas has a heating value of about 1050 Btu/ft 3 .
Operative temperature
Operative temperature is an average of the air temperature of a space and the MRT of the space. It can be measured with a globe thermometer, which is a thermometer inside a black globe.
Particulate filter
Particulate filters remove large particles such as dust and lint from the air and trap them in the filter.
Phytoremediation
Phytoremediation is the direct use of living green plants for in situ, or in place, removal, degradation, or containment of contaminants in soils, sludges, sediments, surface water and groundwater.
polychlorinated biphenyls
Polychlorinated biphenyls (PCBs) are mixtures of synthetic organic chemicals, with physical properties ranging from oily liquids to waxy solids. PCBs were used in many commercial and industrial applications, including building transformers, fluorescent light transformers, paints, coatings, and plastic and rubber products.
rigid steel conduit
Rigid steel conduit is the heaviest type of metal conduit and is connected to junction boxes and other devices with threaded fittings.
Sensible heat
Sensible heat gain from occupants can be assumed to be about 225 Btu/hr, although this varies slightly with occupancy type. Total sensible heat is estimated by multiplying the number of occupants by 225 Btu/hr.
Finish fire rating
Single layers of finish material are rated according to ASTM E84
Steam
Steam is not generally used directly for heating. Typically, steam is piped into a building and used to heat water for water or air heating systems and to drive absorption-type water chillers for air conditioning.
Building Research Establishment Environmental Assessment Method (BREEAM)
The BRE Environmental Assessment Method (BREEAM) is a certified environmental assessment method offered by the Building Research Establishment (BRE), a British organization that provides research-based consultancy, testing, and certification services covering all aspects of the built environment and associated industries.
BIFMA
The Business and Institutional Furniture Manufacturer's Association (BIFMA) maintains two ANSI-approved standards for limiting volatile organic compound emissions from office furniture.
Collaborative for High Performance Schools (CHPS)
The Collaborative for High Performance Schools is a membership-based organization composed of public, private, and nonprofit organizations.
Cradle to Cradle
The Cradle to Cradle (C2C) Certified Product Standard program of McDonough Braungart Design Chemistry (MBDC) certifies products that use environmentally safe materials, are designed so that their materials that can be recovered and reused, use water and energy efficiently in their manufacturing, and are manufactured by socially responsible organizations.
Design equivalent temperature difference
The DETD takes into account the air temperature differences, effects of the sun, thermal mass storage effects of materials, colors of finishes exposed to the sun, and daily temperature range. DETD values are published in tables produced by ASHRAE.
flood test
The area is flooded with 2 in of water for 48 hours, and the interior of the building is inspected for leaks.
conductor
The conductor is the basic material of an electrical system.
Effective aperture
The effective aperture (EA) is the product of two variables: visible light transmittance and window-to-wall ratio.
Heat loss through infiltration
The factor of 1.08 Btu-min/ft 3 -°F-hr accounts for the specific heat of air; that is, the amount of heat that air at a certain density can hold.
frequency
The frequency is measured in units of hertz (Hz), or cycles per second. In the United States, AC is produced at a frequency of 60 Hz. In Europe and other countries, the frequency is 50Hz.
Opening force
The maximum opening force (torque) required to push or pull open interior hinged doors cannot be more than 5 lbf-ft.
watt-hour meter
The most common meter is the watt-hour meter. This registers the use of power over time in kilowatt hours. The meter is placed on the incoming power line in front of any master service switch so that it can operate continuously.
load factor
The ratio of the average power used to the maximum power demand is called the load factor. A low load factor implies an inefficient use of energy and a high demand charge.
Reflectance of interior surfaces
The reflectance of interior surfaces should be as high as possible; minimum reflectance should be 80% for ceilings, 50% to 70% for walls, and 20% to 40% for floors. The wall facing the window should always be as light as possible to improve light distribution.
Resistance of a material
The resistance, R, of a material, is the number of hours needed for 1 Btu to pass through a material of a given thickness when the temperature differential is 1°F.
Direct expansion systems
The simplest type of HVAC system is the direct expansion (DX) system, also known as an incremental unit. A DX system is a self-contained unit that passes non-ducted air over an evaporator, which cools the air. The air is then discharged into the room. Direct expansion units can be through-wall types, roof mounted, or packaged.
Section 01350
The state of California developed its Special Environmental Requirements, Specifications Section 01350 in 2003 for construction of an addition to the state capitol complex.
Embodied energy
The total energy required to extract, produce, fabricate, and deliver a material to a job site, including the collection of raw materials, the energy used to extract and process the raw materials, transportation from the original site to the processing plant or factory, the energy required to turn the raw materials into a finished product, and the energy required to transport the material to the job site.
aluminum conductors and copper conductors
The two most common conductors are copper and aluminum. Aluminum conductors must be larger than copper conductors to carry the same amperage, but they are lighter and generally have a lower installation cost in larger sizes. Copper is more cost effective in small and medium-size wire and cable. Aluminum conductors require special care in installation because joints can loosen and oxides can form, causing resistance and overheating. As a result, the use of aluminum is limited to primary circuits that are installed by skilled workers.
Viewed angle
The viewed angle is the solid angle formed between the measuring position and the outer edges of the object. For example, when sitting close to a fireplace, a person experiences relatively high radiant heat because the fireplace occupies a large angle of view relative to the body.
Visible light transmittance
The visible light transmittance (VLT) is the percentage of visible light that passes through a glazing material. Generally, an EA of between 0.20 and 0.30 provides good daylighting. Thus, if the glazing has a low VLT, the size of the window should be increased.
Window-to-wall ratio
The window-to-wall ratio (WWR) is the net glazing area in a room or space divided by the gross exterior wall area. It does not include window frames or mullions. Small, punched windows have low WWRs, while large, continuous windows have high WWRs.
Yield of a well
The yield of a well is the number of gallons per minute (gpm) it provides. A yield from 5 gpm to 10 gpm is about the minimum required for a private residence.
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There are two basic types of electric circuits: series and parallel.
rainwater and catchment area
To calculate the amount of rainwater available, multiply the catchment area by the average annual rainfall for the region and by a factor, typically 75% or 0.75, to account for evaporation and other losses. One inch of rain yields about 0.6 gal of rainwater per square foot of catchment area.
transformers
Transformers are rated on their capacity in units of kilovolt-amperes (kVa) and are described by their type, phase, voltage, method of cooling, insulation, and noise level. For cooling, transformers are either dry, oil-filled, or silicone-filled.
High-velocity dual-duct system
Two parallel ducts, one carries hot air, and one carries cool air. These two streams of air are joined in a mixing box in proportions to suit the temperature requirements of the conditioned space. However, a dual-duct system is inherently inefficient because both hot and cool air have to be supplied at all times. In addition, moving air at high velocity takes larger, more powerful fans, which need more energy. Air moving at high velocity can cause noise problems in the ductwork. Finally, the initial cost of a dual-duct system is high because of the quantity of ductwork needed.
Underfloor ducts
Underfloor ducts are proprietary steel raceways cast into a concrete floor at regular spacing
VRF advantage
VRF systems are ideal for office buildings, hotels, schools, multifamily residential, and any building with varying loads and different zones. They are also ideal for renovation work because of the small size of piping and the smaller size of compressors and evaporators compared with conventional systems. In addition to saving energy and providing zoning flexibility, VRF systems also provide the advantages of quicker installation than other systems, quiet operation, flexibility in location of equipment, reduced piping, central control, and the ability to continuously monitor energy use as part of a building management system.
Vermiculite
Vermiculite is a hydrated laminar magnesium-aluminum-iron silicate that resembles mica. It is separated from mineral ore, which may include asbestos. When heated during processing, vermiculite expands into wormlike pieces. In construction, it is used for pour-in insulation, acoustic finishes, fire protection, and sound-deadening compounds.
Sweep period of door
When closers are used, the sweep period of the door must be adjusted so that from an open position of 70°, the door will take at least 3 sec to move to a point 3 in from the latch as measured to the leading edge of the door.
Green label plus
a voluntary testing program for carpet, cushion, and adhesive that conforms to CHPS.
solar constant
amount of solar energy that falls in a unit time on a unit area that is 93,000,000 miles from the sun and oriented on a plane perpendicular to the sun's rays. The mean value of the solar constant is 433 Btu/hr-ft 2 . Some of this energy is lost as the energy travels through the earth's atmosphere.
Amount of vapor carried by air and by materials
amount of water vapor carried by air infiltration is 10 to 200 times greater than that carried by diffusion through materials.
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Enthalpy
enthalpy: The total heat in a substance, including latent heat and sensible heat.
Location of air barrier
generally should be located behind the exterior cladding and outside the sheathing. This makes it easier to install, seal, join to other building components, and properly support.
Latent heat
latent heat: Heat that causes a change of state of a substance, such as the heat required to change water into steam. The amount of heat required to change the state of a substance is much greater than the heat required to raise the temperature of the substance (sensible heat). The average value of latent heat per pound of moisture is 1061 Btu.
The amount of combustible materials
limited to 10% of the specific wall or ceiling area to which the material is attached, except in A occupancies, where up to 75% is allowed if the building is fully sprinklered, and in Group R-2 dormitories and dwelling units where up to 50% is allowed if the building is fully sprinklered. In Group B and M occupancies, the amount of combustible fabric partitions suspended from the ceiling is not limited.
Types of Insulation
loose fill, batts, rigid foam boards, spray-on foam, and as part of other construction assemblies such as structural insulated panels.
Fuel efficiency
natural gas 70-80 propane 70-90 no. 2 oil 65-85 anthracite coal 65-75 electricity 95-100
Four main stages in a product's life cycle
raw material acquisition manufacturing use in the building disposal or reuse.
Sol-air temperature
sol-air temperature, a value for outdoor temperature that combines the effects of temperature difference with solar radiation.
If both a vapor retarder and an air barrier are used and they are separate membranes
the air barrier should be 10 to 20 times more permeable to water vapor diffusion than the vapor retarder, to prevent trapping moisture between the two layers.
Thermal insulation
• Cellulose insulation is available in loose-fill form and is made from 80% to 100% postconsumer recycled paper combined with a fire-retardant additive. This material has a low embodied energy. • Compressed straw can be used as infill in structural insulated panels. • Cotton insulation is made from pre-consumer recycled cotton denim scrap material with a small amount of polyester for binding and stability. It also has a low embodied energy. • Glass fiber insulation containing at least 30% postconsumer recycled glass is available in rigid boards, batts, and loose-fill form. • Mineral-fiber insulation, which is made from steel mill slag or basalt rock, is available in rigid boards, batts, and loose-fill form. Most manufacturers use from 50% to 95% recycled material, with 75% postindustrial content being about average. • Spray-on cellulose is manufactured as loose-fill insulation with about the same recycled content as mineral-fiber insulation. The EPA recommends that spray-on cellulose insulation contain at least 75% post-consumer recovered paper. • Perlite is made from volcanic rock expanded by heat. It is used as a lightweight aggregate for plaster and concrete and as loose-fill insulation. • Vermiculite is made from mica expanded by heat. It can be used for loose-fill insulation applications. It is also a component of some spray-applied fireproofing products.
ANSI/ASHRAE/IESNA Standard 90.1, Energy Standard for Buildings, Except Low-Rise Residential Buildings, requires that one of the following three options be used for many commercial buildings.
• Individual air barrier material cannot exceed 0.004 cfm/ft 2 at 0.30 in wg. • Air barrier assemblies cannot exceed 0.04 cfm/ft 2 at 0.30 in wg when tested according to ASTM EI677. • Whole-building air barriers cannot exceed 0.4 cfm/ft 2 at 0.30 in wg when tested according to ASTM E779.
